Two muscular rings called sphincters also provide additional defense against the chemicals in the stomach by moving contents along. The esophageal sphincter separates the esophagus and the stomach. When that muscle doesn’t relax properly, it feels like it is difficult to swallow. On the opposite end of the stomach, the pyloric sphincter regulates the speed at which food moves down to the small intestine.

After the stomach has done its work, the highly acidic mixture of gastric juices and food (known as chyme) leaves the stomach, moves past the pyloric sphincter, and goes into the duodenum before entering the small intestine.

Because the chemicals in the stomach work due to a subtle balance, many problems can arise with the stomach. Some common conditions related to the stomach include: